Environment for
DeveLoping
KDD-Applications
Supported by Index-Structures

de.lmu.ifi.dbs.elki.math.linearalgebra.pca.weightfunctions
Class ErfcWeight

java.lang.Object
  extended by de.lmu.ifi.dbs.elki.math.linearalgebra.pca.weightfunctions.ErfcWeight
All Implemented Interfaces:
WeightFunction

public final class ErfcWeight
extends Object
implements WeightFunction

Gaussian Error Function Weight function, scaled such that the result it 0.1 at distance == max erfc(1.1630871536766736 * distance / max) The value of 1.1630871536766736 is erfcinv(0.1), to achieve the intended scaling.

Author:
Erich Schubert

Constructor Summary
ErfcWeight()
           
 
Method Summary
 double getWeight(double distance, double max, double stddev)
          Get Erfc Weight, using distance / max. stddev is ignored.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

ErfcWeight

public ErfcWeight()
Method Detail

getWeight

public double getWeight(double distance,
                        double max,
                        double stddev)
Get Erfc Weight, using distance / max. stddev is ignored.

Specified by:
getWeight in interface WeightFunction
Parameters:
distance - distance of the query point
max - maximum distance of all included points
stddev - standard deviation (i.e. quadratic mean / RMS) of the included points
Returns:
weight for the query point

Release 0.2 (2009-07-06_1820)